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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: SpQIco1AL67vZkWyVS87J+RgNiqot2W7pKqWVszc5mZysIodbs4GrLMcW9Sm46FIxJv17AXuChg9NujE73V0GOoFe1XNlKxw7ixmQh6UznrpbOoE1aTSIDtFSQk5g4NTzSKxPj955XMvMj5HnulmreK5DHtBguGak+LrinVBzgOMRMKOoUwTchFNOkfi1MaSG9E6/JiIZ6DcKxXCiKYTMA2dz+skdiKIrVWVETQc0Duo+vEoS2gcR10kIzVdmqfvAxWx9q2tuFZ5fRXw0vCkxW+/fMrMJ+SNbTgaISh2cNXw8Qp6oefJ2jyTmn4VJ9b4W15ZX+TcBuOPPD9jDqiV0Epw76ut8YIJ4dsyv9u8srDaad1loxPPi5ZOFuyC+JZvWTs0oTuWHrdIa3o93HlXKoPPdFXKNMurIMKFH5BtgxLpov2dTZ1Zan26MFUqB6My X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 09 Apr 2026 22:02:46.0032 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 60cee4c0-23fa-43e1-23e4-08de9683bb4d X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=3dd8961f-e488-4e60-8e11-a82d994e183d;Ip=[165.204.84.17];Helo=[satlexmb07.amd.com] X-MS-Exchange-CrossTenant-AuthSource: BN3PEPF0000B06C.namprd21.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: LV8PR12MB9359 On 4/3/2026 4:00 PM, Dan Williams wrote: > For drivers that want to fallback to PCI-only operation, immediately > cleanup on attach failure. Otherwise vestigial topology objects are left > until driver unload. > The usage of "attach" here is somewhat ambiguous. Does this mean the attach callback, or cxl_mem attach? Also, I know that providing the attach callback is probably what indicates a driver wants to fallback to PCIe operation, but it's not evident based on the description or contents of the patch. > Signed-off-by: Dan Williams > --- > drivers/cxl/mem.c | 14 +++++++++++++- > 1 file changed, 13 insertions(+), 1 deletion(-) > > diff --git a/drivers/cxl/mem.c b/drivers/cxl/mem.c > index ff858318091f..5e7fa378dd66 100644 > --- a/drivers/cxl/mem.c > +++ b/drivers/cxl/mem.c > @@ -201,7 +201,19 @@ static int cxl_mem_probe(struct device *dev) > struct cxl_memdev *devm_cxl_add_memdev(struct cxl_dev_state *cxlds, > const struct cxl_memdev_attach *attach) > { > - return __devm_cxl_add_memdev(cxlds, attach); > + struct cxl_memdev *cxlmd; > + void *group; > + > + group = devres_open_group(cxlds->dev, NULL, GFP_KERNEL); > + if (!group) > + return ERR_PTR(-ENOMEM); > + > + cxlmd = __devm_cxl_add_memdev(cxlds, attach); > + if (IS_ERR(cxlmd)) > + devres_release_group(cxlds->dev, group); > + else > + devres_remove_group(cxlds->dev, group); > + return cxlmd; > } > EXPORT_SYMBOL_NS_GPL(devm_cxl_add_memdev, "CXL"); > I'm having trouble figuring out how exactly this is supposed to work. I guess I have two questions: 1) What is this devres group doing? There aren't any actions added to it (afaik), so it seems to do nothing? Maybe there's some magic going on here I don't know about? 2) Isn't the memdev already cleaned up if cxl_mem probe fails and attach is provided? What's the extra cleanup happening here?